Why is Isopropanol used after Acetone in cleaning procedures?

[pangru]

In the semiconductor device fabrication procedures, common cleaning recipe includes Acetone and just after it, Isopropanol cleaning.
My question is, Why do we need Isopropanol cleaning after acetone?

As answers of this question says, Isopropanol must be used after acetone cleaning, due to high evaporation rate of acetone
https://www.quora.com/What-are-the-...ing-in-the-order-Acetone-Methanol-Isopropanol

This point is not clear for me, since nobody waits for acetone to evaporate. what will be wrong if I do Aceton + DI water + drying?

 

[ZapperZ]

In the semiconductor device fabrication procedures, common cleaning recipe includes Acetone and just after it, Isopropanol cleaning.
My question is, Why do we need Isopropanol cleaning after acetone?

As answers of this question says, Isopropanol must be used after acetone cleaning, due to high evaporation rate of acetone
https://www.quora.com/What-are-the-...ing-in-the-order-Acetone-Methanol-Isopropanol

This point is not clear for me, since nobody waits for acetone to evaporate. what will be wrong if I do Aceton + DI water + drying?

I'm not sure of all the issues in semiconductor fabrication, but in cleaning stuff for ultra-high vacuum systems, we wipe or clean with acetone and then use isopropanol or ethanol after because acetone tends to leave a residue after it evaporates.

Zz.

 

[Lord Jestocost]

...of all the issues in semiconductor fabrication

More or less the same cleaning procedure for Si-wafers which are contaminated with organic impurities. Isopropanol is an excellent rinse agent for contaminated acetone.

"For substrates contaminated with organic impurities, two-stage substrate cleaning with acetone is recommended to remove organic impurities, followed by isopropanol, which removes contaminated acetone before it can form streaks on the substrate."
[PDF]
Substrate Preparation: Cleaning and Adhesion ... - MicroChemicals

 

[Lord Jestocost]

Why do we need Isopropanol cleaning after acetone?

The question is really good. I always use the standard recipe to remove organic impurities from the surface a various substrates. Maybe, a chemist can answer why it is not recommended to use DI water rinsing directly after acetone cleaning.

 

[pangru]

in cleaning stuff for ultra-high vacuum systems, we wipe or clean with acetone and then use isopropanol or ethanol after because acetone tends to leave a residue after it evaporates.

So, reason to use Isopropanol after Aceton is high evaporation rate of acetone, is it right?

as I understood it is following:>> If I start drying(by Ni gas flow) sample just after acetone cleaning, aceton will evaporate so fast, before I remove by Ni gas-flow,that rinsed particles will redeposit on surface.

 

[pangru]

why it is not recommended to use DI water rinsing directly after acetone cleaning.

That is a point
maybe water can not dissolve acetone

 

[ZapperZ]

So, reason to use Isopropanol after Aceton is high evaporation rate of acetone, is it right?

Did you read what I wrote? If acetone did not leave anything behind, regardless of whether it has a high evaporation rate or not, will we be having this conversation?

Zz.

 

[JRi-z]

Acetone has tendency to oligomerize over time and this reaction can form non-volatile residues. Isopropanol has not that problem.

 

[f95toli]

Indeed, acetone is a good solvent for a lot of things but tend to leave behind some gunk that in turn can be dissolved by isopropanol.
DI water might be able to remove some of those residues (but probably not all of them), but you also have the problem that many materials do NOT like water at all whereas IPA is always safe (if acetone is OK then so is IPA)

 

[pangru]

Did you read what I wrote?

If acetone did not leave anything behind, regardless of whether it has a high evaporation rate or not, will we be having this conversation?

It is clear what acetone leaves something behind.. I wanted to understand the role of its evaporation rate

It seem where are some other reasons why it is good to have IPA after, but evaporation rate is crucial point as well---
thank to all of you for quick and kind explanations,